POI导出Excel并下载

首先在pom.xml添加jar包：

<!-- 导出excel -->

    <dependency>

        <groupId>org.apache.poi</groupId>

        <artifactId>poi</artifactId>

        <version>3.9</version>

    </dependency>

    <dependency>

        <groupId>org.apache.poi</groupId>

        <artifactId>poi-ooxml</artifactId>

        <version>3.9</version>

    </dependency>

导出Excel工具类：

public class ExcelUtil {

    @SuppressWarnings("deprecation")

    public static void excelUtil(HttpServletResponse response,String[] headers,

            List<InsuranceDetailsVO> InsuranceDetailsVOs)

            throws IOException{

        //创建HSSFWorkbook对象(excel的文档对象)

        HSSFWorkbook wb = new HSSFWorkbook();

        //建立新的sheet对象（excel的表单）

        HSSFSheet sheet = wb.createSheet("CSRExport");

        //设置列宽

        sheet.setColumnWidth(0, 20*256);

        sheet.setColumnWidth(1, 25*256);

        sheet.setColumnWidth(2, 24*256);

        .....//生成一个样式

        HSSFCellStyle style1 = wb.createCellStyle();

        //字体设置

        HSSFFont font = wb.createFont();

        font.setFontName("仿宋_GB2312");

        font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);//粗体显示

        font.setFontHeightInPoints((short) 12);

//        style1.setAlignment(HSSFCellStyle.ALIGN_CENTER);

        style1.setAlignment(CellStyle.ALIGN_CENTER);//水平居中

        style1.setVerticalAlignment(CellStyle.VERTICAL_CENTER);//垂直居中

        style1.setFont(font);

        style1.setWrapText(true);

        HSSFRow row1=sheet.createRow(0);

        for (short i = 0; i < headers.length; i++) {

            row1.createCell(i).setCellValue(headers[i]);

            row1.getCell(i).setCellStyle(style1);

        }

        for (int i = 0; i < InsuranceDetailsVOs.size(); i++) {

            HSSFRow row=sheet.createRow(i+1);

            ....这里是给每一行的每一列填充值

        }

        String fileName = "default.xls";

        try {

            fileName = "LD"+DateFormatUtils.getSystemDateByYYYYMMDD()+".xls";

        } catch (ParseException e1) {

            e1.printStackTrace();

        }

        //输出流

        OutputStream os=null;

        try {

             response.reset();

             response.setCharacterEncoding("UTF-8");

             response.setHeader("Content-Disposition", "attachment; filename="+fileName);

//             response.setContentType("application/vnd.ms-excel;charset=utf-8");

             response.setContentType("application/octet-stream;charset=UTF-8");  //流输出

             os = new BufferedOutputStream(response.getOutputStream());

             wb.write(os);

        } catch (Exception e) {

            e.printStackTrace();

        } finally{

            if(os!=null){

                try {

                    os.close();

                } catch (IOException e) {

                    e.printStackTrace();

                }

            }

        }

    }

}